


A promise for a lifetime

by Anchestor



Category: Undertale (Video Game)
Genre: Asexual Gaster, Asexual Grillby, Does it count as major character death if they technically don't die per se, M/M, Marriage, Platonic Male/Male Relationships, Platonic Soulmates, Tags might be spoilery, Time Skips, Veteran Gaster, Veteran Grillby, wedding stuff
Language: English
Status: Completed
Published: 2017-03-04
Updated: 2017-03-04
Packaged: 2018-09-28 06:50:00
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,224
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/10078121
Author URL: https://archiveofourown.org/users/Anchestor/pseuds/Anchestor
Summary: To love, to kiss, to sweetly holdFor the dancing and the dreamingThrough all my sorrows and delightsI'll keep your love beside meI'll swim and sail on savage seasWith ne'er fear of drowningAnd gladly ride the waves of lifeIf you will marry me!Grillby chuckled. “Now that was fun-”“Would you though?”





	

**Author's Note:**

  * For [Silverskye13](https://archiveofourown.org/users/Silverskye13/gifts).



> Kinda-sorta gift for Silverskye13. I've been reading their Platonic Grillster stories (which are pretty damn awesome), and got an idea that would work in the same vein. So I tried to execute the concept in a way I hope they'll like.
> 
> The song that inspired the fic is [For the Dancing and the Dreaming](https://www.youtube.com/watch?v=vCOe4x-LXcE) from How to Train your Dragon 2, and surprise surprise, it features in the fic.
> 
> I'm pretty new to this writing thing, so feedback would be appreciated ^^

“Gaster! Food’s done!” Grillby hollered as he started scooping the broth into bowls. But there was no response. A preliminary glance around their little campfire, and he saw that Gaster had migrated from the log he had been sitting on to the ground, and to a much more horizontal position. Lazybones.

“Hey. Gaster. Wake up. You can sleep once you’ve eaten.” He continued, and accompanied his words with a gentle nudge with his leg.

“I’m not sleeping, I’m meditating.” Gaster mumbled. His voice sounded rather sleepy, though. But he pushed himself from the ground and resumed his spot on the log, yawning a thank you as Grillby handed him his portion for the evening.

“Mmmm! It’s really good!” Gaster said after taking a hearty sip of the hot broth, the heat of the food properly waking him up from his definitely-not-a-nap. “Have I ever told you that you should become a cook or something?”

Gaster rolled his eyes. “Only at least every other time I cook. And it’s nothing _that_ special. It just tastes good because you’re hungry.”

“Well, _maybe_. But it’s still better than anything I could make!” Gaster chuckled, letting the bowl warm his hands. The evening was chilly after all, and their joint tent was at the edge of the camp, vulnerable to the cool autumn winds. The cold didn’t really bother Gaster, Grillby even less, and it was nice to have a bit of distance from the hustle and bustle found at the heart of the camp.

“So what do you have planned to do then?” Gaster asked. Grillby’s only answer was a confused look.

“After the war, I mean. If you don’t want to be a ‘cook or something’.” He clarified.

 “I don’t know. Haven’t thought that far, really.” Grillby shrugged. “What about you? Going back to doctoring?” He asked, eager to direct the subject away from himself. He really didn’t want to plan a future that might never happen. War was war after all.

 “Yeah, probably. Helping people instead of fighting sounds nice. Although I’ve been thinking about if I could study more sciences. I mean, there has been is so much advancement recently! They have discovered new texts by these ancient Greek philosophers, and there is so much fascinating stuff there!” Gaster explained, waiving his free hand around excitedly. And as much as Grillby liked seeing his friend light up like this, he was also concerned for the safety of the broth and by extension their little campfire.

“But I’ve also thought about getting some peace and quiet for a change. Settling down, getting married. Kids. All that nice homely stuff.” Gaster smiled. 

“Married, huh.” Grillby mulled out loud.

“I remember when a friend of mine –the niece of the doctor who trained me- got married. It was such a beautiful ceremony. And the cake was delicious!” Gaster reminisced. “Hey! Maybe that could be a job for you!”

“What? Being a wedding planner?” Grillby asked skeptically.

“No! A baker! I bet you’d make amazing cakes!” Gaster was getting excited again. At least he had put the bowl on the ground, so it probably wasn’t going to spill. But now there was nothing to hold back his gesturing. Grillby subtly shifted away before an ecstatic hand accidentally smacked him in the face.

“I don’t know. I’ve never baked anything.” Grillby sipped his own broth. Better enjoy it before it cooled.

“Nonsense! Baking can’t be that hard! And if I ever get married, I’d want no-one else baking my wedding cake!” Gaster finished his declaration with a firm nod and an oh-so-serious look. Grillby chuckled.

“Fine. I’ll make you your wedding cake. As long as your hypothetical fiancée doesn’t oppose.”

 

 

 

 

“Gaster? Could you move a bit? I need to swipe the table.” The bar was mostly empty by now, only a few customers in one of the booths. They’d leave soon enough, but as it was nearly closing time, Grillby had decided to start to prepare for locking the place up for the night.

“Mmmmh.” Gaster answered, lifting his crossword puzzle. “Hey. What’s a ten letter word for ‘accompanies a bride’? Last letter is ‘d’.”

Grillby pondered a bit. “Bridesmaid?”

“Hey, that fits! Thanks, firefly.” Gaster scribbled the word down quickly. The door opened and closed as the last patrons left, leaving the bartender and the scientist alone in the bar.

“Hey. Did you know that the original purpose of bridesmaids were to confuse evil spirits? That’s also why brides have veils, it hides the face.” Gaster grinned. He liked to drop little factoids like that when he could. Grillby didn’t mind at all.

“I did not know that.”

“Also works against jealous suitors. Although that’s what the best man was originally for.”

Grillby paused to give Gaster a questioning look. The skeleton grinned and folded the crossword away. Explaining things was one of his favourite things about being a scientist.

“So back in the day, arranged marriages were sadly pretty standard among richer people. So it wasn’t uncommon for the bride’s actual sweetheart to crash the wedding to steal the bride away! Or just some jealous alternative suitor. Lots of bride stealing was going on, apparently. Anyway! So that the groom doesn’t have to watch his back all the time, a best man was employed. Literally. And by best it meant best swordsman the groom could afford to hire. But since that’s kind of expensive, it shifted to be whichever groom’s friend was the best sword fighter of the group. And when sword fighting and bride stealing went out of style, the role evolved to what it is today: the groom’s best friend.” Gaster finished.

“Huh. I never knew humans had such weird wedding customs.” Grillby thought out loud. “And what’s going to happen if it’s two brides getting married? Or two grooms?”

“Half the evil spirits or double the manpower to fend off suitors I suppose?” Gaster shrugged as he unfolded his crossword again. He paused as he thought of something, and chuckled.

“You’d make the best best man ever.”

Grillby smiled, though it didn’t reach his eyes. He could expect where this was going. “I guess I’m pretty handy with the sword.”

“That wasn’t really what I meant”, Gaster said, with that odd smile of his that made the fire elemental feel warm inside. “You’re meticulous, responsible, and reliable. You’d never loose the rings or anything. Also you have an alcohol licence, so the bachelor party would be a hoot!” Gaster spun on his barstool to emphasize the hootness. As the momentum died down, Gaster was facing Grillby again. “And you definitely are my best friend.”

Grillby knew his flame was flickering through all sorts of happy colours. They’d know each other long enough to know what they meant to each other. But it was nice to hear it out loud nonetheless.

“Well. You’re my best friend too. And when the day comes, I promise to fend off anyone who tries to steal your fiancée at the altar.” Grillby said with playful seriousness.

“Huh. I guess I’ll have the best man picked out then.” Gaster grinned. “Now to figure out who to actually marry!”

 

 

 

 

 

“Grillby-! Grillbyyyy! Hey! Grillby!” Gaster weaved his way through the small crowd that was occupying the bar. Earlier that morning Gaster had finally managed to fix the jukebox that was sitting in the corner of the bar. Apparently most of Snowdin had heard that the (by default) most popular place to hold the town’s gatherings now had music available, and had collectively decided to throw an impromptu party to test the new attraction. A full house was, of course, good news for Grillby. Especially after Gaster suggested that some of the tables were to be moved to the sides to make a small dance floor. Dancing is tiring and makes people thirsty, so even if fewer tables meant less food orders, creating demand for drinks was proving to be quite profitable. The downside was that this had trapped Grillby behind the counter for nearly the whole of the evening. But now, as the evening was beginning to slowly turn into night, and people were starting to trickle out, Grillby would have the chance to sit down for a moment. But Gaster had other plans.

“Grillby come dance with me!” Gaster demanded enthusiastically as he zoomed behind the counter and started dragging his friend towards the dance floor. But alas, he was met with resistance.

“Gaster, you know I can’t dance-“

“I’ll lead.”

“I don’t want to bump into people-”

“Most people are leaving so there is plenty of room.”

“But the bar-”

“ _Can wait five minutes._ Come _on_ , firefly, live a little.” Gaster whined. How a skeleton could do puppy eyes, the world may never know, but Gaster somehow managed to do it. “What’s the point of having a jukebox if you never get to enjoy it. And I even have a song picked out.”

Grillby probably was biased about the matter, but he was sure that Gaster’s pout could melt even the most hardened of heart.

“You’re lucky I like you as much as I do.” He sighed with a smile, as he allowed himself to be pulled to the dance floor.

“I know.” Gaster beamed at him. The pair took a waltz position as the song started with a slow tempo. A male voice started singing.

_I'll swim and sail on savage seas_  
_With ne'er fear of drowning_  
_And gladly ride the waves of life_

Grillby fumbled with getting his legs to follow the rhythm. The song was even apparently sea themed, why? Why had he agreed to this?

_If you will marry me_  
_No scorching sun_  
_Nor freezing cold_

“Firefly.” Gaster whispered. Grillby looked up from his feet. “It’s rude not to pay attention to your dance partner.” Gaster’s smile was encouraging, and it helped the elemental relax. He was dancing with his best friend, his favourite person in the whole wide world. It would be fine.

_Will stop me on my journey_  
_If you will promise me your heart_  
_And love me for eternity_

The pace of the song picked up, and the new rhythm was easier to follow, even if their dancing was a bit improvised. Now a female voice started singing instead of the man.

_My dearest one_  
_My darling dear_  
_Your mighty words astound me_  
_But I've no need for mighty deeds_

Grillby was sent twirling, and as he returned, he ended up with his back flush against the skeletons chest, so that Gaster was hugging him from behind.

_When I feel your arms around me_

The man was singing again.

_But I would bring you rings of gold_  
_I'd even sing you poetry_

Suddenly Gaster dropped on one knee, and Grillby circled him, hopping over Gaster’s legs. This was surprisingly fun!

_And I would keep you from all harm_  
_If you would stay beside me_

The woman answered.

_I have no use for rings of gold_  
_I care not for your poetry_  
_I only want your hand to hold_  
_I only want you near me_

Gaster tightened his grip. The tempo was speeding up again, and the pair was spinning in a fast polka-like dance instead of the pseudo-waltz they had started with. Now both the male and female voices were singing together.

_To love, to kiss, to sweetly hold_  
_For the dancing and the dreaming_  
_Through all my sorrows and delights_  
_I'll keep your love beside me_

_I'll swim and sail on savage seas_  
_With ne'er fear of drowning_

Grillby lifted Gaster up for one final twirl in the air-

_And gladly ride the waves of life_  
_If you will marry me!_

-and Gaster slid into Grillby’s arms, they were flushed together, their foreheads leaning onto each other, eyes locked, both trying to catch their breaths.

Grillby chuckled. “Now that was fun-”

“Would you though?” Gaster abruptly asked. And as soon as the question was in the air, all joy dropped from the skeletons face. All of a sudden he looked… scared.

“…Would I what?” Grillby asked slowly. He didn’t like seeing Gaster this… nervous.

“Outside?” Gaster asked in a tight wrung voice, pulled away and fled before Grillby could answer.

“Gaster, wait!” Grillby called, as he followed the skeleton outside into the cool darkness of the evening.

Gaster was standing there, facing away, tightly hugging himself. Grillby wasn’t sure if he should approach him or not. It was tearing him apart.

“It’s… something I’ve thought about lately. A lot. A lot lot.” Gaster sounded so unsure, so unlike the enthusiastic scientist Grillby usually saw. Gaster turned around, and his smile looked just as unsure as his words sounded.

“What I mean is… You know that I love you, right? I love you so, _so much_ , and I… You… You are like family to me, _are_ family to me; you are my soul mate, and I-! I just… I want to be with you, be there for you, and make you happy, always! Always.” Gaster was fidgeting with his hands, looking everywhere but at Grillby.

“Gaster…” Grillby started, but Gaster interrupted him.

“And it’s okay if you don’t want to! I understand! I just- I just thought- I thought it would be- that you should know- and and and, it’s fine, really, if you don’t want to, but I thought I’d ask- I- I…” Gaster trailed off. He looked like he was _this close_ to crying.

Grillby took his friend’s hands in his own so that they’d stop shaking. “Gaster. You are going too fast. Breathe.” He said in a calming voice, and waited for Gaster to actually breathe a moment.

“First of all: yes. I do know that you love me. And you are my soul mate, too. Now. What did you want to ask me?”

Gaster looked at Grillby. “Would you marry me?” his voice was little more than a whisper.

Grillby paused for a moment. Gaster wanted to…? Now he was feeling nervous too.

“Gaster. I love you. But… doesn’t marriage have some… implications? I… I never thought you felt… _that_ way about me. I mean. We don’t even kiss that often-”

“And I like the way we are! We don’t have to change that! The kissing and cuddling is plenty enough for me!” Gaster interjected. “But that doesn’t mean that yours isn’t the first face I want to see when I wake up in the morning. And… I want to be with you. Share my whole life with you. For better or worse, for sickness and in health.” The skeleton looked scared again. But hopeful, too.

“Yes.” Grillby breathed out.

“What?”

“Yes. I want to marry you. I’d like that very much.”

Gaster’s face lit up. “Really?”

“Really really.” And Grillby kissed Gaster.

 

 

 

 

 

“Helloooo my beautiful betrothed!”

“Gaster, don’t use words like betrothed. Your interns will figure out how old you are.”

“But it’s such a fun word! Betrothed, betrothed, betrothed!” It was hard not to smile with how giddy Gaster sounded, even over the receiver.

“Well, is there any reason in particular you called your _betrothed_ during working hours?”

“In fact there is! Good news is that I checked with anyone for allergies, and nothing major came up. So if you want to do some practice cakes, everything is fine.” The pair had decided to make the wedding a small event, and the reception was to be held at the bar. Grillby had insisted that he wanted to bake the wedding cake himself, despite how much Gaster protested: _“It’s our special day firefly, you don’t have to take care of everything!”_ But Grillby had promised. Even if it had been so many years ago. They had agreed to make more precise plans –the date, decorations, invitations- tonight. But…

“The bad news is that work might get late. I’m not sure when I can leave, so we might have to postpone planning night.” Gaster explained apologetically.

“That’s alright. What’s going on?” Grillby asked. He hoped that Gaster simply wasn’t grabbing all the work he could get again. The skeleton had a bad habit of biting more than he could chew.

Gaster groaned. “The Core has been misbehaving. The central readings have gone bonkers! So I’ll have to check if the problem is with the indicators or with the generator. And the latter case is going to take all night to fix.”

“I see. Do you think you’ll be free to plan tomorrow?”

“If nothing unexpected happens.”

“Okay. See you tomorrow then.”

“Yes. Bye Grillby! I love you!”

“Love you too, Gaster.”

 

 

 

 

 

Something woke Grillby up that night. He didn’t know what it was. He didn’t know where it came from, or what had caused it. The only way he could describe it was the soul crushing feeling of utter _wrongness_. Like in one foul swoop the world had been bent off its rails. 

The worst part? _He felt like he should know what was going on._ Like it was at the tip of his tongue, just beyond reach. But he couldn’t grasp it. His throat felt tight, his soul was pounding so fast it hurt. Grillby scrambled to find his phone. But there was no one to call. He screamed into the night. But nobody came.

 

 

 

 

 

Grillby had kept a lot of stuff across the years. His oldest possession was his sword, hidden in the back of his closet. He didn’t want to look at it; he didn’t want the reminder of the war he had fought in. (Not that he remembered that much of it, it had been a long long time ago after all, he told himself.) But he couldn’t find it in himself to get rid of, either.

Some things he kept out of convenience. Somewhere in his kitchen cupboards was a frying pan with a broken handle. Grillby wouldn’t have bothered, but it was a _really good_ frying pan. He had hoped that he could sometime either get the handle fixed, or find a new one just like it.

But the ring he could never figure out.

It was hidden in a small box in one of the drawers of his nightstand. The only piece of jewellery he owned. Grillby didn’t know where it had even come from, he was sure he hadn’t bought it himself. But he couldn’t remember anyone giving it to him either.

Some nights, when he was lying in bed, sleep eluding him, he’d look at the ring. It was a simple silver band. Without inscriptions. He liked how the cool metal felt as he examined the ring. It was quite beautiful, even if it didn’t have decorations.

He’d toy with it sometimes, running his touch around and around the smooth surface. Felt the curve on his fingertips. Watched as his flame reflected on the metal.

But he never put it on.

Eventually he’d return the ring to where it belonged. Encased safely in the soft black satin of the little black box, hidden in one of the drawers of his nightstand.

There was something about the little silver ring he never could figure out. Something that made him feel a little bit better about the world as a whole, but also made him feel empty inside. Something nostalgic, something melancholy. Something bittersweet.

Grillby didn’t know where the ring had come from, or why he had it. But he kept it.


End file.
